Dynamic Boost on Dell G15 5520

I have the latest bios and proper nvidia driver installed on debian. As per nvidia driver instruction says,

SBIOS support for Dynamic Boost

Run the following command to check if the SBIOS supports Dynamic Boost:

nvidia-settings -q DynamicBoostSupport

http://us.download.nvidia.com/XFree86/Linux-x86_64/515.48.07/README/dynamicboost.html

DB can be enabled if it is supported in bios, and it’s supported by dell. But the query result is 0.

How can I enable DB under linux?